Coal cleaning device



April 9, 1935. J, MQGREW 1,996,821

COAL CLEANING DEVICE Filed March 30,- 1951 Patented Apr. 9, 1935 i y 1395 8215 UNITED STATES PATENT OFFICE 1,996,821 I 7 cont. CLEANING DEVICE JameshMoGrew, Pittsburgh, Pa. Application March 30,1931, Serial No. 526,243

sclaims. '(Cl. 209-474) The invention relates to improvements in coal shown. Refuse can be crushed and retreated cleaning devices, in which drag-chain conveyors with middle products, if so desired. operate on a stationary table, with either an air Drag-chains l, 8, 9 and 55 are returned by current, or water, assisting in the stratification means of tail sprockets 25, 2?, 28 and 29. Tail of the materials of diiferent specific gravities; sprockets 26, 2?, 28 and 29 are supported on 5' and the objects of the improvements are, first, to. shafts 35, which rest in take-up bearings 3|, provide a simpler and cheaper method of cleanwhich are on foundation 2. V ing coal; second, to eliminate the self-destructive Drive sprockets l2, l3, l4 and i5 are supportedelement in former methods, where moving tables on shafts 32, which rest in bearings 33, and are are employed; third, to make cleaner separation driven by motor 3%. 10 than other air-process tables; and fourth to avoid Motor 34 operates through sprockets 35, 36, 31, wetting of the fine coal, as in the water washeries. 38, 3S, and drive chains 40, 4!, 42 and 43, and by One form of the invention is illustrated in the means of variable speed transmissions 44 and accompanying drawing, in which Figure 1 is a speed reducers 45, 46 and 47 to get the desired Vertical section of the entire device; Figure 2, a speeds with which to drive shafts 32. 15

plan view of table foundations and air duct, with Fan H5 is driven by motor 48 through variable table removed; Figure 'o is a. plan view of piers speed transmission 49. e for drive supports; Figure 4 a plan view of table Side plates 58 form sides of table- I, and carry with parts above removed; Figure 5, a plan view guide angles Si, 52, 53 and 54 also post 55, which showing part of one drag-chain, Figure 6 a supports guide angles 56, 51, 5B and 59. Guide 20 transverse sectional view through device near angles 5!, 52, 53, 54, 5G, 51, 58 and 59 support'and center of table; Figure 7 a longitudinal section guide drag-chains l, 8, 9 and H1. Posts 5 are of spill plates, on a larger scale; Figure 8 a sectied by tie bar 59. I tional view of side plates, on a larger scale, show- Pipe supports 6| act as beams under table I, ing angle guides; and Figure 9, an end view of assisting in its support. r 25 water connection employed, when water is used. Water can be used in place of air, by substitut- The table lis a wooden frame resting on founing plates 62 in place'of perforated metal sheets dations 2, and covered with perforated metal 3, and forcing water up by gravity pressure sheets 3. Plate 4 extends from table back far through narrow spaces between plates 62. This is enough to receive coal from bin 5, with the aid done by means of a bent plate 63, with end 30 of rotating feeder 6. plates 64 welded. on each end of it. End plates Drag-chains '1, 8, 9 and ID with cross-bars ll, 64 are drilled and tapped for a water pipe at one propelled by drive sprockets l2, l3, l4 and i5, end, and a plugat the other end, for a cleandrag the coal over table I. The coal is stratified out. Bent plate 63 with gasket 65 is bolted to by the aid of a current of air forced up through plates 62. The upward'flow of the water assists 35 perforated metal sheets 3, by fan l6, through air in the Stratification of the coaland its impurities, duct l'l. Drag-chains 1, 8, 9 and I0 then take .In cleaning large coal, water is preferable to air, the coal and refuse out over spill plates l8, I9, 26 In the water process only two drag chains and and 2 I, at the end of the table. two spill plates need be used. The fan, and other The refuse heavier than coal, which stratifies parts not needed, can be eliminated. The same at the bottom, is dragged by drag-chain 1, over is true in retreating refuse and the middle prodspill plate 18, and falls into refuse chute 22, thence not, to reclaim what good coal may be in them. to refuse conveyor not shown. I am aware that prior to'my invention, coal The coarse coal, which stratifies immediately cleaning devices have been inoperation, using above the refuse, is dragged by drag-chain 8, over water and air to assist in the Stratification be- 45 spill plate l9, and fallsinto coal chute 23, thence fore separation. I therefore do not claim their to conveyor not shown. use broadly; but

A middle product of fine coal mixed with slate I claim: dust, found by experience to stratify above the 1. In a machine for grading divided material, a coarse coal, is dragged by drag-chain 9, over a supporting table for said material, meansfor .0 spill plate 25, and falls into chute 24, thence loading material at one end of said table and to conveyor not shown. discharge means at the other end'of said table,

The clean fine coal, which-stratifies on top, is a plurality of endless chains arranged in supereeed b hain 0, v r spill plate nd posed relation above said table adapted to con-1 I falls into coal chute Z5, thence t0 conveyor not vey the material from the charging to the discharge end of said table, means carried by said chains for engaging the'material on said table to stratify the same-according to the division thereof with the heavier particles at the bottom of the table, saidmeans being further operative to convey theldivided materials in the direction of the-discharge means and means for exerting fluid pressure upwardly through the material. 4 2. In a machine for grading divided material,

a supportingtable, for said material, means for charging. material at one end of said table and spill plates in superposed relation at the other end of said table, a plurality of endless chains;

said chains, and means for regulating the relative speeds of said chains.

3. In a machine for grading divided material, a perforate supporting table for said material, means for exerting fluid pressure upwardly through the perforations in the table, a plurality of endless chains arranged in superposed relation above said table, said chains being provided with material engaging members extending transversely of. the table to stratify the material according to the division thereof, a charging chute at one end of said table, spill plates at the other end of said table, said spill plates being in superposed relation and cooperating with the respective chains to direct the divided materials to difierent chutes, drive mechanism for said chains, and means for controlling the relative speedsof'said chains independently of each other.

JAMES MCGREW. 

